Open House Chicago is coming back bigger and better this year.

The weekend event, from Oct. 13-15, will open up more than 170 architectural rarities to the public for free, up from 150 last year, according to the Chicago Architecture Center.

And for the first time, two parties will kick off opening night: A party open to the public at the architecture center’s building at 111 E. Wacker Dr.; and a members-only party on the 33rd floor of Willis Tower.

The rest of the weekend features self-guided tours at culturally and architecturally significant buildings in more than 20 neighborhoods.

New in this year’s lineup is Uptown’s Riviera Theater, an ornate concert venue originally built in 1917 as a movie theater.

People can also visit the childhood home of Walt Disney in Hermosa and the National Cambodian Heritage Museum in Ravenswood.

For more information, visit openhousechicago.org.